RU2659814C1 - Rotor of the synchronous reactive electric machine - Google Patents

Abstract

FIELD: electrical equipment.

SUBSTANCE: invention relates to the field of electrical equipment, in particular to the rotor of synchronous reactive electrical machine. Rotor (10) of the synchronous reactive electrical machine operating directly in the electrical power supply network has shaft (7). At least in separate portions, the said rotor (10) is provided with axially laminated plates (13). Rotor (10) is made as the reactive rotor having predetermined number of poles, formed by the flux conducting portions (15), and, in particular, the non-magnetic barrier portions (16) for the individual plates flux. In addition, the rotor (10) has at least one cell, formed by the substantially axially passing electric conductors, which, at the rotor each end face, are connected by the short-circuiting rings (14). Axially passing conductors (19) are in the radially outer region of at least separate substantially axially arranged one after another barrier sections (16) for flux, wherein the winding conductive rods inner diameter (21) is determined by of the quantity of used conductive material.

EFFECT: improvement of starting properties.

9 cl, 6 dwg

Description

The present invention relates to a rotor, in particular a rotor of a synchronous reactive electric machine, operating directly in the power supply network, the rotor having an axis, and this rotor provided with axially laminated plates at least in some sections, the rotor being made as a jet rotor having a predetermined number of rotor poles which are formed by sections conducting the flow, and, in particular, non-magnetic barrier sections for the flow of individual plates, the rotor having at least one cell formed passing essentially axially electric conductors, which are connected by short-circuiting rings on each end side of the rotor.

In addition, the invention relates to a synchronous reactive electric machine and a method for manufacturing a rotor of a synchronous reactive electric machine.

The rotors of rotating dynamo-electric jet engines are designed in a batch and anisotropic manner. Conducting sections and barrier sections are made for magnetic flux in the circuit of individual plates. Due to this, the fluxes along the magnetic axes d and q are different.

The rotor thus has distinct poles. These poles are obtained due to the fact that various inductances are constructively created along the d axis and along the q axis of the rotor. In this case, the rotor surfaces are supplied, for example, with a gear structure, or flow barriers are cut out in the rotor plates.

For example, in US 4,795,936 A1, a rotor is described in which the rotor inductance changes due to a notch. The middle of the d axis is provided with a soft magnetic material and gives way to the flow. This design creates different magnetic resistances along the magnetic axes d and q of the rotor, thereby clearly expressed rotor poles being formed there. The inductance along the d axis is higher than the inductance along the q axis. Thus, the magnetic resistances along these axes also turn out to be different. The inductance difference is therefore decisive for the torque at the output of the reactive electric machine. In order for the synchronous jet motor to be started directly in the power supply network, for example, 400 V, 50 Hz and synchronized with the frequency of the network, it is necessary to additionally provide a short-circuited cage in the rotor for direct start to full voltage.

For example, in US 2006/0108888 A1, a rotor with short-circuit rods is shown. In this case, the rods in the sheet steel of the rotor are separated by jumpers from the flow barriers. Thus, locally bounded conductive rods are present. These jumpers, however, act negatively on the properties of the jet rotor, since part of the magnetic flux in this region is closed and can no longer participate in the creation of torque. As a result, the efficiency, as well as the power density of the synchronous reactive electric machine, decreases.

Likewise, a rotor is known from WO 2014/166555 A2, in which the flow barriers are completely flooded. Increased material consumption increases the inertia and cost of the rotor. In addition, when using the injection molding method, additional external support is necessary for the geometry of the sheet steel during the casting process, since under the influence of pressure in the flow barriers, the radially external jumpers of the core package can be overloaded by their tensile strength during casting.

Based on this, the present invention is based on the task of creating a rotor of a synchronous reactive electric machine, which is simple to manufacture and, nevertheless, ensures the launch of a synchronous reactive electric machine directly in the power supply network.

The task in the rotor, in particular, operating directly in the power supply network of a synchronous reactive electric machine, the rotor having an axis, and this rotor is provided with axially-loaded plates at least in some sections, the rotor being made as a reactive rotor having a predetermined number of rotor poles, which are formed by sections conducting the flow, and, in particular, non-magnetic barrier sections for the flow of individual plates, and the rotor has at least one cell formed by passing essentially axially electric conductors, which are connected by short-circuiting rings on the end faces of the rotor, are solved due to the fact that axially extending conductors are located in the radially external region of at least separate flow barriers located essentially axially one after another.

The solution to this problem is also provided by a method of manufacturing a rotor, in particular, operating directly in the power supply network of a synchronous reactive electric machine, the rotor having an axis, and this rotor is equipped with axially-charged plates at least in some sections, the rotor being made as a reactive rotor having a predetermined the number of rotor poles formed by the sections conducting the flow, and, in particular, non-magnetic barrier sections for the flow of individual plates, the rotor having at least th least one cell formed substantially axially extending electrical conductors which are on the end sides of the rotor are connected by short-circuiting rings, which process is characterized by the following steps:

- cutting down plates with a given geometry of sheet steel,

- axial packaging of these plates in a burnt package of sheet steel,

- pouring a predetermined amount of electrically conductive non-magnetic material into a predetermined number of flow barrier sections while rotating and / or swinging the rotor in an auxiliary device.

The electrical conductors of the formed squirrel cage of the rotor are located at the radially outer ends of at least some of the flow barriers of the rotor core package. This ensures, among other things, effective acceleration of a reactive electric machine directly in the power supply network - i.e. even without intermediate electrical switching on the valve converter.

The conductive non-magnetic materials provided as conductors are pure aluminum (aluminum 99.7), aluminum alloys, copper, copper alloys, a conductive material bonded in plastic or polymer resin, non-ferrous metals in the form of powder in plastic or polymer resin, as well as carbon nanotubes in plastic or polymer resin, preferably with thin short fibers.

Preferably, the material of such conductors is a metal and / or a metal alloy. According to one embodiment of the invention, the conductor in at least one region comprises at least one of the following materials: copper, aluminum, magnesium, an alloy, preferably an aluminum alloy, in particular silumin.

The sections conducting the flow are in a known manner separated from each other by non-magnetic regions blocking the flow. In this case, the barrier sections for the flow are non-magnetic, i.e. in particular, due to the fact that they do not contain ferromagnetic material, i.e., for example, cuttings contain air. In the rotor according to the invention, in several or all areas of the flow barriers, an electrically conductive, non-ferromagnetic aggregate is placed in the radially external regions of these flow barriers. By "electrically conductive" it should be understood here that the aggregate has high electrical conductivity, in particular, a conductivity value of more than 105 C / m (Siemens per meter), preferably more than 106 C / m.

A non-ferromagnetic material in the sense of the present invention is, for example, a completely non-magnetic material, for example, ceramic with carbon nanotubes or a polymer with carbon nanotubes, or paramagnetic or diamagnetic material.

In order to influence the pulsation of the rotor torque of a synchronous reactive electric machine, i.e. To smooth out the pulsations, the rotor poles are preferably beveled, intersecting, or stepwise, as viewed in the direction of axial length. In this case, of course, you need to pay attention to the fact that mowing or stepwise arrangement is provided by the manufacturing process of axially extending conductors, which will be described later, and a cell inside the rotor can be created. It is important that, when mowing or stepping, there are axially extending conductors.

The rotor proposed by the invention is obtained, in particular, due to the fact that the axially laid lined rotor package is installed in an auxiliary device, a short-circuit half ring (Kurzschlussringschale) is placed on one end side and filled with electrically conductive non-magnetic material in liquid form to a predetermined filling level.

Similarly, short-circuiting half-rings can be placed on both end faces of a packaged sheet steel package and filled with electrically conductive non-magnetic material in liquid form to a predetermined filling level.

Then, by flowing this conductive material into the flow barriers and using the subsequent and / or connected centrifugal casting method, this material inside the provided flow barriers is forcibly introduced into the radially external regions of these flow barriers, where it hardens and thus forms at least one short-circuiting rod - those. one electrical conductor - at the radially outer edges of the flow barriers.

In order to prematurely cure the electrically conductive material in the flow barriers, the burden pack of sheet steel of the rotor is preheated and / or during the process.

Thus, the conductive material remains in its liquid state longer and can be better positioned within the corresponding flow barriers within the manufacturing process, in particular due to centrifugal forces.

The rotor according to the invention, in comparison with conventional rotors, has a reduced mass and, thus, a reduced moment of inertia. This also leads to resource savings. In addition, the manufacture of the shape of the metal sheet - i.e. the provision of a suitable sheet stamp is relatively simple, since no separation, respectively, of jumpers between the grooves of the conductors and the sections conducting the flow, and the barrier sections for the flow in the plates is required. Conductor cross section, i.e. the cross section of the cell rod is regulated only by the volume of the conductive material suitable for spillage and / or the inner diameter of the short-circuiting half rings.

The presence of reference jumpers inside the core package does not adversely affect the magnetic flux, as well as the efficiency of the reactive electric machine according to the invention.

The manufacturing method of the inventive rotor is suitable for a wide variety of cross-sections of rods and a different number of poles. Thus, according to the invention, it is possible with one single form of rotor plate to produce a synchronous jet motor with or without a cell.

The rotor according to the invention gives the advantage that the regions of the flow barriers, respectively, the barrier portions of the flow with the filler located in them form the rods of the rotor cell and, thus, are integrated into the reactive rotor proposed by the invention. Together with short-circuited rings and rods of the cell, i.e. with the rotor cage, the synchronous jet motor can now be started asynchronously, respectively, in a simple way to equalize the load fluctuations that prevent the synchronous rotation of the rotor. Thus, after asynchronous start, acceleration or load oscillations, the rotor rotates independently in synchronous mode. The rotor, therefore, is the rotor of a synchronous jet motor with a significantly higher efficiency, respectively, a higher power density than a comparable induction motor, since there are almost no losses in this rotor. In synchronous rotation mode, i.e. when the rotor rotates at a rotational speed of the rotor magnetic field of the stator, there is no relative motion / slip of the stator field with respect to the rotor field, respectively, there is no induction in the rotor rods of the rotor cell.

Due to the selection of filler conductors - i.e. electrical resistance set in this way - it is also possible to optimize the parameters of the start of the rotor regardless of the parameters of its synchronous rotation. The hardened aggregate is preferably so rigid that it stabilizes the rotor even from centrifugal forces, so that the rotor is designed for operation with a speed of more than 3000 rpm (revolutions per minute), in particular more than 7000 rpm.

According to one modification of the invention, one electrically conductive and non-ferromagnetic plate is located on opposite axial ends of the laminated steel sheet package, by means of which the cell rods are electrically connected, and thus these plates form a short-circuited squirrel cage rotor ring. These plates can be made preferably by injection molding or injection molding at a low cost. The plates can be made from the filler of conductors used in a particular case.

Another low-cost possibility of regulating the electrical resistance of a squirrel cage rotor is obtained according to an embodiment in which the corresponding effective section of the plate conductor is between two conductors, i.e. the cell rods are so small that these plates in this section of the conductor have a greater electrical resistance than the conductors, respectively, the cell rods. For example, the plate thickness measured in the axial direction is so small that the current path in the transition from one cell rod to the next in this plate has a greater electrical resistance than in the cell rods. The plates can be made in the same way as a short-circuit ring, i.e. with a cut-out, so that a conductor cross section can also be set.

According to one embodiment, at least one intermediate plate is also provided axially inside the laminated package of sheet steel, which can also be made of the material of the conductive rods or the material of both plates located on the end sides of the ends of the laminated package. This provides the advantage of increasing the mechanical stiffness of the rotor and thereby increasing the rotor speed can be achieved. In addition, in this way, a predetermined stepwise arrangement between two axially consecutive parts of the lined rotor package can be simply ensured. The offset between the axially adjacent poles of the rotor can thus be adjusted up to one pole division.

The material of the conductors and the short-circuiting rings of these conductors on the end sides of the ends of the laminated sheet of sheet steel is filled with a conductive material in a durable unit, which makes it possible to especially easily perform the rotor of a dynamoelectric machine.

The present invention finally provides an electric drive device that comprises a dynamoelectric machine with a rotor according to one embodiment of the present invention. This dynamoelectric machine is intended for use as a synchronous jet electric motor or as an asynchronous motor. The advantage of this dynamoelectric machine is that it can be started in asynchronous mode, and operated in synchronous mode with high efficiency. In the case of an induction motor, the advantage is that with a small load, the rotor can also be in synchronism with the rotating field of the stator, and due to this, a synchronous reactive mode is obtained, due to which the electric losses in the rotor are minimized.

In the simplest case, the electric drive device is a separate dynamoelectric machine. The drive device according to the invention may, however, comprise several dynamoelectric machines, i.e. at least one additional dynamoelectric machine with a corresponding rotor can be added to the described dynamoelectric machine, which is made in accordance with one embodiment of the inventive rotor. All machines in this embodiment are connected to one common inverter. With such a group drive, as a rule, the problem arises of providing this common inverter with a synchronous mode for all dynamoelectric machines. In the drive device according to the invention, there is no such problem, since the “rotor falling out of synchronism” independently accelerates with its rotor cage again to a synchronous speed.

It may also be provided in the drive device that one of the dynamoelectric machines has a rotor that is not made according to the present invention. The inverter in this case can be made for the synchronous mode of this one electric machine. All other electric machines in this case, due to their ability to start asynchronously, can also work from this inverter.

The present invention, as well as other preferred embodiments of the invention, are described in more detail using several embodiments as examples; while the drawings show the following:

FIG. 1 is a partial longitudinal section of a synchronous reactive electric machine,

FIG. 2 - section of the rotor,

FIG. 3 is a perspective view of a longitudinal section of a rotor,

FIG. 4 is a perspective view of a rotor,

FIG. 5 - section of the rotor, and

FIG. 6 is a schematic block diagram of a rotor manufacture.

In FIG. 1 shows a partial longitudinal section of a synchronous reactive electric machine having a stator 2, which is axially made laden, and on the ends of the stator 2 there are frontal parts 3 of the winding, which are part of a winding system not shown in more detail, which is located in the grooves 4 of the stator 2. The rotor 10 is separated from it by the air gap. The rotor 10, as will be discussed in more detail below, is a jet rotor with a short-circuit ring 14 on each end side of the rotor 10. This is a short the shorting ring 14 is part of the conductive rods not shown in this image, which are located in the corresponding recesses of the rotor 10. Between the stator 2 and the rotor 10, electromagnetic interaction occurs, which causes the rotor 10 and, therefore, the shaft 8 to rotate around axis 7.

The stator 2 is located in the housing 6, which, in turn, is supported by a bearing 9 on the shaft 8. In order to provide sufficient cooling, a fan 12 is schematically shown, which through the indicated axial cooling channels 11 in the rotor 10 and, accordingly, cooling channels 5 in the stator 2 provides air exchange and, thereby, heat transfer in a reactive electric machine 1.

In FIG. 2 shows a side view of the rotor 10, which in this embodiment is made four-pole, and such a four-pole implementation is obtained due to the location of the sections 15 that conduct the flow, and the barriers 16 of the stream. The flow barriers 16 in this embodiment have central support ribs 17 in order to absorb radial forces, in particular, centrifugal forces during operation of the jet electric machine 1. Through axial drilling 18, the shaft 8 is connected to the rotor 10 without the possibility of rotation. Short-circuiting ring 14 is located in the radially outer end of the rotor 10, in direct contact with the end side of the rotor 10.

However, the short-circuit ring 14 can also be located at a distance from the end side of the rotor 10, for which gasket elements are provided that are axially between the short-circuit ring 14 and the end side of the burdened package 13 of sheet steel. These electrically non-conductive cushioning elements are removed after manufacture or remain on the rotor 10.

In FIG. 3 is a longitudinal sectional view of a cut rotor 10, and, in contrast to the above image of FIG. 2, it is shown how the short-circuiting ring 14 extends axially beyond the end side of the rotor 10, not directly adjacent to this end-side of the rotor 10. It also shows how the conductive rods 19 extend from the short-circuiting ring 14 and extend along the entire axial length package 13 of the core of the rotor 10.

In FIG. 4, in addition to the previous figures, it is shown that in the region of the core package 13, the conductive rods 19 are located inside the radial support ribs 20, and now only short-circuiting rings 14 are axially outside the package 13 of the rotor core 10.

In FIG. 5, another section of the metal sheet of the four-pole rotor 10 is shown in cross-section of the rotor 10, in which the flow barriers 16 do not have central support ribs 17. Otherwise, this shape of the metal sheet corresponds to the shapes shown in the previous figures. It is noteworthy here that according to the invention, the conductive material is only at the radially outer ends of the flow barrier portions 16. Conductive material has entered these external locations of one or more portions of the flow barrier 16 shown schematically in FIG. 6 way. Moreover, it was in the region of the short-circuit ring 14 that a short-circuit half-ring 23 was installed, which ends flush with the end side of the rotor 10 and thus can be filled with liquid electrically conductive material, which is distributed along the axial length of the burst bag 13 of the rotor 10 of the corresponding section of the flow barrier 16.

Due to the rotation 22 and / or the rocking movement of the device and, thus, the package 13 of the core of the rotor 10, the liquid electrically conductive material is distributed along the outer radial edges of the flow barrier sections 16. The cross section of each of the conductive rods thus obtained is preliminarily determined by the amount of conductive material used, which, in turn, forms the inner diameter of 21 conductive rods.

Additionally, after cooling of the material of the conductors in the flow barrier portions 16, the same or similar aggregate is supplied to the short-circuiting half rings 23 in order to achieve the desired cross-section and / or electrical conductivity of the short-circuiting ring 14.

Such synchronous reactive electric machines 1 are used, in particular, for driving fans or compressors, but can also find very different applications in group drives.

Claims (13)

1. The rotor (10), in particular, operating directly in the power supply network of a synchronous reactive electric machine (1), moreover, this rotor (10) has an axis (7), and this rotor (10) is provided with axially laden at least in some areas plates (13), and the rotor (10) is designed as a jet rotor having a predetermined number of rotor poles (10) formed by sections (15) conducting the flow, and, in particular, non-magnetic barrier sections (16) for the flow of individual plates, moreover, the rotor (10) has at least one cell formed substantially axially extending electrical conductors which are at each end of the rotor are connected by short-circuiting rings (14), characterized in that axially extending conductors (19) are located in the radially outer region of at least separate flow barrier portions (16) arranged substantially axially one after the other, the amount of conductive material used determining the inner diameter (21) of the conductive winding rods. 2. The rotor (10) according to claim 1, characterized in that the poles of the rotor (10) in the axial direction are made with parallel axes, beveled or crossed. 3. The rotor (10) according to claim 2, characterized in that, with an axial stepwise arrangement of the parts of the rotor charge package (10), the barrier sections (16) for the flow of these parts of the charge package of sheet steel are rotated by a predetermined angle so that axial the formation of a passing axially electric conductor (19). 4. The rotor (10) according to any one of the preceding paragraphs, characterized in that at least one short-circuit ring (14) is surrounded by a short-circuit half ring (23). 5. A method of manufacturing a rotor (10) operating directly in the power supply network of a synchronous reactive electric machine (1), the rotor (10) having an axis (7), and this rotor (10) is provided with laminated plates (at least in some areas) (13) moreover, the rotor (10) has a predetermined number of poles formed by the sections (15) conducting the flow, and, in particular, non-magnetic barrier sections (16) for the flow, which includes the following steps: - cutting down plates with a given geometry of sheet steel, - axial packaging of these plates in at least one charge package (13) of sheet steel, - pouring a predetermined amount of electrically conductive non-magnetic material into a predetermined number of flow barrier sections (16) while rotating and / or swinging the rotor (10) in an auxiliary device, - moreover, during pouring and / or immediately after it, the rotor (10) rotates around the axis (7) at a relatively high speed, so that the electrically conductive non-magnetic material is on the radially external edges of the flow barriers (16) and freezes there, forming electrically conductive rods that short-circuit rings (14) are electrically connected to each other on the end faces of the rotor (10) of the burden package (13) made of sheet steel. 6. The method according to p. 5, characterized in that a predetermined amount of electrically conductive non-magnetic material is provided in at least one short-circuited half-ring (23), which is open radially from the inside and in the axial direction ends with a laminated sheet of steel sheet (13) along the radially outer edge . 7. The method according to p. 5 or 6, characterized in that the charge package (13) of sheet steel before pouring a conductive non-magnetic material is heated to a certain temperature. 8. A synchronous reactive electric machine (1) with a rotor (19) according to one or more of the preceding paragraphs, and this synchronous reactive electric machine (1) is suitable for operation directly in the power supply network. 9. The use of at least one synchronous reactive electric machine (1) according to claim 8 as a separate drive or in a group drive, in particular in the drive of fans or compressors.

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